TITLE(image @@ Display a color image)
USAGE(
image(x, y, z, zlim, col=heat.colors(12), ...)
BLANK
)
ALIAS(image)
ARGUMENTS(
ARG(x,y @@ locations of grid lines at which the values in LANG(z)
are measured.  These must be in ascending order.
By default, equally spaced values from 0 to 1 are used.)
ARG(z @@ a matrix containing the values to be plotted (LANG(NA)s are allowed).)
ARG(zlim @@ the minimum and maximum LANG(z) values for which colors
will be plotted.  Each of the given colors will be used to color
an equispaced interval of this range).
ARG(col @@ A list of colors such as that generated by LANG(LINK(rainbow)),
LANG(LINK(heat.colors)), LANG(LINK(topo.colors)), LANG(LINK(terrain.colors))
or similar functions.)
ARG(DOTS @@ graphical parameters for LANG(LINK(plot)) may also be
passed as arguments to this function.)  
)
DESCRIPTION(
Creates a grid of colored or gray-scale rectangles with colors
corresponding to the values in LANG(z).  This can be used to display
three-dimensional or spatial data.
The functions LANG(LINK(heat.colors)), LANG(LINK(terrain.colors)) and
LANG(LINK(topo.colors)) create heat-spectrum (red to white) and
topographical color schemes suitable for displaying ordered data, with
LANG(n) giving the number of colors desired.
)
NOTE(
This function is based on an interpreted function
written by Thomas Lumley (thomas@biostat.washington.edu).
)
SEEALSO(
LANG(LINK(contour)),
LANG(LINK(heat.colors)),
LANG(LINK(topo.colors)),
LANG(LINK(terrain.colors)),
LANG(LINK(rainbow)),
LANG(LINK(hsv)),
LANG(LINK(par)).
)
EXAMPLES(
data(volcano)
x <- 10*(1:nrow(volcano))
y <- 10*(1:ncol(volcano))
image(x, y, volcano, col=terrain.colors(100),axes=FALSE)
contour(x, y, volcano, levels=seq(90, 200, by=5), add=TRUE, col="peru")
axis(1, at=seq(100, 800, by=100))
axis(2, at=seq(100, 600, by=100))
box()
title(main="Maunga Whau Volcano", font.main=4)
)
